Electrical cutout



Sept. 19,- 1950 R. s. GRAHAM 2,522,573

' ELECTRICAL CUTOUT F;iled Nov. 19, 1948 s sums-sheet 1 \\v INVENTORATTORNEY p 1950 R. G. GRAHAM 2,522,573

ELECTRICAL CUTOUT Filed Nov. 19, 1948 3 Sheets-Sheet 2 /Z I 20wavny/pflW I I m FIG. 2

FIG; 5 ATTORNEY p ,1950 R. G. GRAHAM 2,522,513

ELECTRICAL CUTOUT Filed May. 19, 1948 3 Sheets-Sheetb' FIG. 7

INVENTOR Rev G. GRAHAM v ATTORNEY Patented Sept. 19, 1950 ELECTRICALCUTOUT Roy G. Graham, St. Louis, Mo., assignor to James R. KearneyCorporation, St. Louis, Mo., a corporation of Missouri ApplicationNovember 19, 1948, Serial No. 61,097

10 Claims. (01. 200-114) This invention relates generally to electricalcutouts of the type adapted to interrupt an electrical circuit uponrupture of a fuse link, which constitutes a part of the output, becauseof the occurrence of an electricalfault in the circuit in which thecutout is interposed, and more specifically to a housed cutout of thisgeneral type the housing of which is provided with a movable door onwhich is mounted acircuit-completing fuse tube and which door drops toits open position on rupture of the fuse link of the cutout so as tocompletely remove the fuse tube from the circuit and produce asubstantial gap in the circuit, the predominant object of the inventionbeing to provide a cutout of this type which, because of its improvedconstruction and arrangernent is capable of performing its intendedfunction in an improved and highly efiicient manner. 1 Fig. 1 is avertical section illustrating the improved cutout of this invention.

Fig. 2 is a horizontal section taken on line 2-2 of Fig. 1. r

Fig. 3 is a fragmentary vertical section taken on line 3-3 of Fig. 1.

Fig. 4 is a fragmentary vertical section taken on line 4-4 of Fig, 1.

Fig. 5 is a fragmentary vertical section taken on line 55 of Fig. 1.

Fig. 6 is a fragmentary vertical section taken on line 6-6 of Fig. 1.

Fig. 7 is a horizontal section taken on line I-I of Fig. 1.

Fig. 8 is a fragmentary vertical section illustrating the lower portionof the cutout as it appears when the door of the cutout has beenreleased for movement to its open position.

i In the drawings wherein is shown for purposes of illustration, merely,one embodiment of the invention, A designates generally the improvedcutout of this invention which is intended particularly for use ininterrupting circuits carrying currents of relatively high amperages.The cutout A comprises a housing I which is formed of porcelain, orother suitable electrical insulating material, said housing being openat its front and being provided with a door 2 which normally closes saidopen front of said housing and is provided with a hand grip 2' formanually actuating same to open and closed positions when desired. Thehousing I is provided with a hanger structure 3 that is secured to thehousing by fastening means 4 and which is adapted to be suitablyattached to a supporting structure, a crossarm 13, for instance.

(Disposed in the upper portion of the housin I is an upper contactsupport 5 which is U-shaped in plan (Fig. 2), the rear, bridge portionof said contact support being arranged in contact with an inner faceportion of the rear wall of the housing I. The upper contact support 5is secured in place by a pair of stud bolts 6 which are anchored bycement or solder 1 in openings 8 formed in said rear wall of thehousing, and nuts 9 are received by the forward, screwthreaded portionsof said bolts for securing the upper contact support in place. Thesenuts 9 serve also to secure to the forwardface of the bridge portion ofthe upper contact support 5 a suitable incoming terminal structure IU,said incomin terminal structure having clamped thereto by clamping boltsII and a clamping bar I2 an incoming electrical conductor I3.

The outer portions of the spaced legs of the upper contact support 5have pivoted therebetween, through the instrumentality of a pivotelement I4, the upper contact I5 of the cutout A, this upper contactbeing U-shaped with its bridge portion at the bottom, and said bridgeportion of said upper contact is provided with a V-shaped notch I5!which serves a purpose to be hereinafter set forth. The lower portion ofthe upper contact I5 is urged forwardly by a torsioned coil spring II;which is coiled about the pivot element I4 and whose opposite endportions H engage pins II andIB supported, respectively,

by the upper contact support 5 and the upper contact I5 '(Fig. 1). Also,the upper contact has secured thereto by a bolt I9 an electricalconductiveclip 20, said clip being attached to a conductor 2| whoseopposite end is provided with an electrical conductive clip 22 which issecured by a bolt 23 in electrical contact with a portion of the incominterminal structure I0 (Fig. 3).

Arranged in the lower portion of the housing I of the cutout Ajis alower contact support 24 which is shaped as is shown to good advantagein Fig. 1. In other words, the lower contact support 24 is U-shaped inplan and the rear face of its bridge portion contacts with a forwardface portion of the rear wall of the housing I. The lower contactsupport is secured in place by means of a pair of stud bolts 25 whichare anchored in openings 26 formed in the rear wall of the hOllSing I bybodies of cement or solder 21, as is shown in Fig. 1, said stud bolts 25having mounted on their forward, screwthreaded end portions nuts 28. Thenuts 28 secure the lower contact support 24 in place within the housingI, and, additionally, these nuts secure to the forward face of thebridge portion of said lowercontact support an upwardly extended portion29 of an outgoing terminal structure 39. The outgoing terminal structure39 is constructed and arranged in accordance with the incoming terminalstructure 19, said outgoing terminal having clamped thereto by clampingbolts 3| and a clamping bar 32 an outgoing conductor 33. The lowercontact support 24 includes transversely spaced, downwardly andforwardly extended p01- tions 34 which are somewhat hook-shaped at theirlower and outer ends, the hook-shaped formation of said spaced portionsproviding bearing cavities 35 which perform a function to be hereinafterset forth.

Supported for pivotal movement between spaced upper portions of thelower contact support 2-1 by a pivot element 36 is a lower contact 31,said lower contact being U-shaped in plan with its bridge portion at therear thereof, and the transversely spaced, forwardly extended legs ofsaid lower contact are shaped as shown to good advantage in Fig. 1 andare provided with notches 38 formed in their lower edges which serve afunction to be hereinafter set forth. The forward portion of the lowercontact 37 is urged downwardly by a torsional coil spring 39 which iscoiled about the pivot element 36 and whose opposite end portionsrespectively engage a pin 49 supported by the lower contact support 31and a lower edge portion of the bridge portion of said lower contact, asis shown in Fig. 1. Also, a conductor 4| is provided for conductingelectrical energy from the lower contact 31 directly to the outgoingterminal structure 30, this con ductor 4! being provided at one end withan electrical conductive clip 42 which is secured in electrical contactwith the outgoing terminal structure 90 by a bolt 43, and being providedat its op-= posite end with an electrical conductive clip 44 which issecured in electrical contact with the lower contact 31 by a bolt 45.

Mounted on the door 2 is a fuse link housing which includes an upperbracket 4.5 that is tubular in shape and is provided with lateralextensions 4'! which receive screws 48 for securing said bracket to thedoor 2. The fuse link housing includes a tubular structure 49 the upperportion of which is received within the lower portion of the upperbracket 46 and which extends downwardly from said upper bracket to apoint located a slight distance above the bottom of the door 2. A lowerportion of the tubular structure 49 is seated in a curved cavity formedin a saddle 59 which is secured to the door 2 of the cutout by means ofscrews and this saddle 59 has secured thereto by screwthreaded elements52 a hinge member 53, said hinge member having a vertical saddle portion53' which is provided with a curved cavity in which a portion of thetubular structure is seated. The hinge member 53 is provided with a pairof transversely spaced, rearwardly and downwardly extended arms 54 whichare provided at their lower ends with outwardly extending trunnions 55,said trunnions bein the outer extended end portions of a shaft 55' andsaid trunnions being seated in the bearing cavities 35 of the lowercontact support so as to support the door 2 for hinging movement to openand closed positions.

Extended rearwardly from upper portion of the hinge members 53 is a pairof laterally spaced extensions 5B which receive therebetween an endportion of a link 51, said link being pivotally connected to saidextensions by a pivot element 58.

4 The opposite end portion of the link 5! is pivotally attached to alatch member 59 through the instrumentality of a pivot element 59', saidend portion of said link being disposed between a pair of verticallyextended, transversely spaced flanges 60 formed on said latch member,and the pivot element 59 is extended through openings formed throughsaid flanges and through said end portion of said link. The latch member59 includes an upper, transversely extended bar portion Bl from which isextended downwardly a portion 62, and formed on the rear face of saidlatch member is an inverted U-shaped flange 53 (Fig. 5). Also, theportion 62 of the latch member 59 is provided witha screwthreadedopening that receives the screwthreaded stem of a bindin post 64, saidbinding post comprising a bolt with which a washer 64 is associated.

Pivotally attached between the lower portions or the spaced flanges 66of the latch member 59 is the outer end portion of the short leg 56a 01'a bell crank lever 68, such pivotal attachment of said short leg of saidbell crank lever being obtained through the instrumentality of a pivotelement 61. The bell crank lever 56 is supported for swinging movementby the shaft 55' whereon it is disposed between the arms 54 of the hingemember 53 (Fig. 6). The longer leg 66!) of the bell crank lever normallyextends downwardly slightly and forwardly, as is shown in Fig. 1, sothat its forward end portion underlies the lower end of the tubularstructure 49, and said forward end portion of said longer leg of saidbell crank lever 96 is partially circular in shape, as shown at 650 inFig. 7, to provide a semicircular 9611 which serves a purpose to behereinafter set forth.

The improved cutout of the present invention includes a fuse link 68which is arranged within the tubular structure 49 of the fuse housing46. The fuse link 68 may be provided with a head 68 which is forcedagainst a, shoulder within the upper bracket 46 by a suitablescrewthreaded cap 69, the fuse link being provided with a fusiblesection 16 (Fig. l) which is disposed within the upper portion of thetubular structure 49. When the cutout A is arranged for normal operationthe lower portion of the fuse link extends out of the lower end of thetubular structur 49 and engages the rear wall portion of the cavity Rdat the forward portion of the longer leg of the bell crank lever (Fig.'7), saidv fuse link extending rearwardly and upwardly along said longerleg of said bell crank lever to its rear end and then projects upwardlyto the rear face of the latch member 59, where said fuse link is loopedabout the shank of the binding post 64 and is engaged within theinverted U-shaped flange 63 by the washer 64 so as to securely clampsaid fuse link to said latch member.

When the cutout is in its eifective position for normal operation,opposed portions of the transverse bar portion 6| of the elevated latchmember 59 are seated in the notches 38 formed at the lower edges of theopposed forwardly extended portions of the U-shaped lower contact 31.The latch member 59 is held in its elevated position by the fuse link 68which engages the forward portion of the longer leg of the bell cranklever, as has been previously explained herein, so as to retain saidbell crank lever and the latching member in the positions in which theyare shown in Fig. l, where the door 2 is securely locked in its closedposition by engagement between said latching member and said lowercontact. When an electrical fault occurs in the circuit in which thecutout is interposed which is of suflicient magnitude, the fusiblesection I of the fuse link is ruptured. This separates the fuse link andinterrupts the circuit, of which the fuse link forms a part, andreleases the longer leg of the bell crank lever 66 from the restraintnormally imposed on it by the intact fuse link and permits said bellcrank lever to swing to the position in which it is shown in Fig. 8. Asa result of such movement of the bell'crank lever 66 the pivot elements59' and 61 are lowered with the result that the entire latch member 59is lowered so as to completely disengage the transverse bar portion 6|of the latch member from the notches 38-01 the lower contact 31. On suchdisengagement of the latch member 59 from the notches of the'lowercontact the upper'portion of the door 2 is forced outwardly by outwardlymovement of the lower portion of the upper contact l acting in responseto force exerted by the torsional coil spring 16, whereupon the doorswings outwardly and downwardly about the trunnions 55 to provide asubstantial gap in the interrupted circuit. In this connection it is tobe noted that the upper bracket 46 is seated in the notch l5 of theupper contact l5.

When it is desired to re-fuse the cutout after its door has droppedopen, as explained above, the door assembly is removed from the housingI of the cutout by disconnecting the trunnions 55 from the bearingcavities of the lower contact support 24, and. a new fuse link isassembled with the door assembly. Thi is accomplished by removing thecap 69 at the top of the upper bracket 46 and passing the new fuse linkdownwardly through the tube structure 49 and out of the lower endthereof. The cap 69 is then replaced and the fuse link is drawn intoengagement with the lower leg of the bell crank lever 66 so as to 1.

move the latch member 59 to its effective position. The door is thenreplaced in association with the housing I of the cutout and said dooris moved upwardly and inwardly about the trunnions 55 to its closedposition, the inwardly moving transverse bar portion 6| of the latchmember 59 engaging the inclined lower edges of the forward, spacedportions of the lower contact 3! so as to raise the forward portion ofsaid lower contact against the force of the torsional coil spring 39 toa sufficient degree to permit upper edge portions of the transverse barportion of the latch member to enter the notches 38 of said lowercontact 31.

The normal current path through the cutout Alfrom the incoming conductorI3 is by way of the incoming terminal structure ID, the conductor 2|,the upper contact l5, the upper bracket 46, the fuse link 68, the latchmember 59, the lower contact 31, the conductor 4|, the outgoing terminalstructure 39, and the outgoing conductor 33. Also, if desired, thetubular structure 49 may be comprised of an outer tube 49a of Bakelite,or other suitable electrical insulating material, and an inner tube 49bformed of horn fiber, or other suitable material which is characterizedby the ability to give off gas in the presence of the heat of anelectrical arc. Thus the presence of an inner tube formed of material socharacterized will tend to extinguish any electrical are which may beproduced within the tubular structure 49 on rupture of the fusiblesection of the fuse link.

. I claim:

.;.=;1. An electrical cutout comprising a housing formed of electricalinsulating material, a door hingedly supported relative to said housingfor closing an open portion of said housing, an upper contact and alower contact arranged in spaced relation within said housing, a fuselink housing mounted on said door, a fuse link arranged within said fuselink housing for electrical connection with said upper contact andextended from the lower end thereof, a movable latch member adapted. forlatching engagement with said lower contact, means for supporting saidlatch member from said door for independent movement including anelement supported for swinging movement and adapted to impart movementto said latch member, said element being engaged by the intact fuse linkto maintain the latch member in a position where it is in latchingengagement with said lower contact so as to retain the door in itsclosed position and said element being released upon rupture of the fuselink to cause said latch member to be released from latching engagementwith said lower contact and permit said door to move to its openposition.

2, An electrical cutout comprising a housing formed of electricalinsulating material, a door hingedly supported relative to said housingfor closing an open portion of said housing, an upper contact and alower contact arranged in spaced relation within said housing, a fuselink housing mounted on said door, a fuse link arranged within said fuselink housing for electrical connec tion with said upper contact andextended from the lower end thereof, a movable latch member adapted forlatching engagement with said lower contact, means for supporting saidlatch member from said door for independent movement including anelement comprising a bell crank lever supported for swinging movementand adapted to impart movement to said latch member, said element beingengaged by the intact fuse link to maintain the latch member in aposition where it is in latching engagement with said lower contact soas to retain the door in its closed posi tion and said element beingreleased upon rupture of the fuse link to cause said latch member to bereleased from latching engagement with said lower contact and permitsaid door to move to its open position.

3. An electrical cutout comprising a housing formed of electricalinsulating material, a door hingedly supported relative to said housingfor closing an open portion of said housing, an upper contact and alower contact arranged in spaced relation within said housing, a. fuselink housing mounted on said door, a fuse link arranged within said fuselink housing for electrical connection with said upper contact andextended from the lower end thereof, a movable latch member adapted forlatching engagement with said lower contact, means for supporting saidlatch member from said. door for independent movement including a linkand an element supported for swinging movement and adapted to impartmovement to said latch member, said element being engaged by the intactfuse link to maintain the latch member in a position where it is inlatching engage-ment with said lower contact so as to retain the door inits closed position and said element being released upon rupture of thefuse link to cause said latch member to be released from latchingengagement with said lower contact and permit said door to move to itsopen position.

4. A electrical cutout comprising a housing formed of electricalinsulating material, a door hingedly supported relative to said housingfor closing an open portion of said housing, an upper contact and alower contact arranged in spaced relation within said housing, a fuselink housing mounted on said door, a fuse link arranged within said fuselink housing for electrical connection with said upper contact andextended from the lower end thereof, a movable latch member adapted forlatching engagement with said lower contact, means for supporting saidlatch member from said door for independent movement including a linkand an element comprising a bell crank lever supported for swingingmovement and adapted to impart movement to said latch member, saidelement being engaged by the intact fuse link to maintain the latchmember in a position where it is in latching engagement with said lowercontact so as to retain the door in its closed position and said elementbeing released upon rupture of the fuse link to cause said latch memberto be released from latching engagement with said lower contact andpermit said door to move to its open position.

5. An electrical cutout comprising a housing formed of electricalinsulating material, a door hingedly supported relative to said housingfor closing an open portion of said housing, an upper contact and apivotally supported lower contact arranged in spaced relation withinsaid housing, a fuse link housing mounted on said door, fuse linkarranged within said fuse link housing for electrical connection withsaid upper contact and extended from the lower end thereof, a movablelatch member adapted for latching engagement with said lower contact,means for supporting said latch member from said door for independentmovement including a link and an element comprising a bell crank leversupported for swinging movement and adapted to impart movement to saidlatch member, said element be- Tmg engaged by the intact fuse link tomaintain the latch member in a position where it is in latchingengagement with said lower contact so as to retain the door in itsclosed position and said element being released upon rupture of the fuselink to cause said latch member to be released from latching engagementwith said lower contact and permit said door to move to its openposition.

- 6. electrical cutout comprising a housing formed of electricalinsulating material, a door hingedly supported relative to said housingfor closing an open portion of said housing, an upper contact and apivotally supported spring urged lower contact arranged in spacedrelation within said housing, a fuse link housing mounted on said door,a fuse link arranged within said fuse link housing for electricalconnection with said upper contact and extended from the lower endthereof, a movable latch member adapted for latching engagement withsaid lower contact, means for supporting said latch member from saiddoor for independent movement including a link and an element comprisinga bell crank lever supported for swinging movement and adapted to impartmovement to said latch member, said element being engaged by the intactfuse link to maintain the latch member in a position where it is inlatching engagement with said lower contact so as to retain the door inits closed position and said element being released upon rupture of thefuse link to cause said latch member to be released from latchingengagement with said lower contact and permit said door to move to, itsopen position.

'7. An electrical cutout comprising a housing formed of electricalinsulating material, a door hingedly supported relative to said housingfor closing an open portion of said housing, a pivotally supported uppercontact and a lower contact arranged in spaced relation within saidhousing, a fuse link housing mounted on said door, a fuse link arrangedwithin said fuse link housing for electrical connection with said uppercontact and extended from the lower end thereof, a movable latch memberadapted for latching engagement with said lower contact, means forsupporting said latch member from said door for independent movementincluding an element supported for swinging movement and adapted toimpart movement to said latch member, said element being engaged by theintact fuse link to maintain the latch member in a position Where it isin latching engagement with said lower contact so as to retain the doorin its closed position and said elemen being released. upon rupture fthe fuse link to cause said latch member to be released from latchingengagement with said lower contact and permit said door to move to itsopen position.

8. An electrical cutout comprising a housing formed of electricalinsulating material, a door hingedly supported relative to said housingfor closing an open portion of said housing, a pivotally supportedspring urged upper contact and a lower contact arranged in spacedrelation with in said housing, a fuse link housing mounted on said door,a fuse link arranged within said fuse link housing for electricalconnection with said upper contact and extended from the lower endthereof, a movable latch member adapted for latching engagement withsaid lower contact, means for supporting said latch member from said doofor independent movement including an element supported for swingingmovement and adapted to impart movement to said latch member, saidelement being engaged by the intact fuse link to maintain the latchmember in a po sition where it is in latching engagement with said lowercontact so as to retain the door in its closed position and said elementbeing released upon rupture of the fuse link to cause said latch memberto be released from latching engagement with said lower contact andpermit said door to, move to its open position.

9. An electrical. cutout comprising a housing formed of electricalinsulating material, a door hingedly supported relative to said housingfor closing an open portion of said housing, a pivotally supportedspring urged upper contact and a lower contact arranged in spacedrelation within said housing, a fuse link housing mounted on said door,a fuse link arranged within said fuse link housing for electricalconnection with said upper contact and extended from the lower endthereof, a movable latch member adapted for latching engagement withsaid lower contact, means for supporting said latch member from saiddoor for independent movement including an element supported forswinging movement and adapted to impart movement to said latch member,said element being engaged by the intact fuse link to maintain the latchmember in a position where it is in latching engagement with said lowercontact so as to retain the door in its closed position and said elementbeing released upon rupture of the fuse link to cause said latch memberto be released from latching engagement with said lower contact andpermit said door to move to its open position, said pivotally supportedspring urged upper contact engaging a portion of said fuse link housing.

10. An electrical cutout comprising a housing formed of electricalinsulating material, a door hingedly supported relative to said housingfor closing an open portion of said housing, a pivotally supportedspring urged upper contact and a lower contact arranged in spacedrelation within said housing, a fuse link housing mounted on said door,a fuse link arranged within said fuse link housing for electricalconnection with said upper contact and extended from the lower endthereof, a movable latch member adapted for latching engagement withsaid lower contact, means for supporting said latch member from saiddoor for independent movement including an element supported forswinging movement and adapted to impart movement to said latch memher,said element being engaged by the intact fuse link to maintain the latchmember in a position where it is in latching engagement with said lowercontact so as to retain the door in its closed position and said elementbeing released upon rupture of the fuse link to cause said latch memberto be releasedfrom latching engagement with said lower contact andpermit said door to move to its open position, said pivotally supportedspring urged upper contact engaging a portion of said fuse' link housingwhich is formed of electrical conductive material.

ROY G. GRAHAM.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,070,759 Steinmayer, Feb. 16,1937 2,076,681 Steinmayer Apr. 13, 1937 2,264,203 Fry Nov. 25, 1941

